A network device such as a router may be designed to route packets of information through a network. In some instances, there may be a need to model the performance of a router. This may be appropriate, for example, to test router performance as implemented in an actual network. Conventional modeling techniques, however, may be unsatisfactory. For example, conventional modeling techniques may not use an actual routing table to model performance. Rather, they may make certain assumptions regarding a network and implement those assumptions using static packet sizes and routes. Furthermore, they may take these results and attempt to extrapolate theoretical worst and best case performance. The assumptions and extrapolations may introduce error into performance results. Consequently, there may be a need for improved performance modeling techniques for network devices.